im using this for my truss rod

1) should i cut a small amount off the already threaded part so it doesnt get in the way? or should i just leave it?

2) also, what should i use to cut the truss rod? hacksaw?

3) how far away from the end of the neck should i thread the truss rod, 2 inches right?
1. You shouldn't have to cut the threaded part at all.

2. A hacksaw will work fine, just make sure you cut straight.

3. The truss rod should end in the middle of the neck heel.